Online detection system based on cable partial discharge positioning

Abstract

The invention discloses an online detection system based on cable partial discharge positioning, and relates to the technical field of partial discharge positioning, the online detection system comprises a screening module, a detection module, a compensation module and a display module, the similarity between a first spectrogram and a partial discharge spectrogram is calculated, a second positioning signal or a first jump signal is sent, and a second positioning signal or a second jump signal is sent; calculating the ratio of the non-overlapping part to the area of the first spectrogram, sending a first frequency regulation and control signal, matching an ideal detection frequency, detecting the refined segments according to the ideal detection frequency, obtaining partial discharge amplitudes, selecting the partial discharge amplitude with the maximum value, and setting a second number corresponding to the partial discharge amplitude as a partial discharge fault point. According to the method, the cable is subdivided into sub-cables and numbered, the detection accuracy is improved, the working efficiency is improved by calculating the interference degree, ensuring the effectiveness of signals, automatically generating a spectrogram and managing task serial numbers, the coordinates and types of partial discharge fault points are visually presented, and the safety and reliability of the cable are greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of partial discharge positioning, and in particular to an online detection system based on cable partial discharge positioning. Background Art

[0002] In recent years, cable partial discharge positioning technology has continued to develop. Emerging high-frequency sensors and digital signal processing technologies have improved the detection accuracy of partial discharge signals, making the positioning of partial discharge faults more accurate. A comprehensive platform integrating multiple detection technologies and data analysis methods has been developed, which can comprehensively evaluate the cable system and ensure the safety and reliability of transportation facilities in cable monitoring of urban rail transit and highways.

[0003] At present, a cable partial discharge positioning system and positioning method are disclosed in a Chinese invention patent with publication number CN 113671307 A. This method uses an optical signal through an optical synchronization module to synchronize the working clocks of all information acquisition modules, and the optical synchronization module, the acquisition module and the monitoring center module are connected by an optical cable. The advantages of low optical signal propagation delay and no electromagnetic interference can be utilized to improve the partial discharge fault judgment efficiency and positioning accuracy. However, the related technology does not have a basis for compensating for the detection error, which is not conducive to the accuracy of the system. The partial discharge is not preliminarily screened according to the actual use of the cable, which is easy to cause invalid workload or heavy workload. Summary of the invention

[0004] The technical problem solved by the present invention is that: the related art does not compensate for the detection error, which is not conducive to the accuracy of the system, and does not conduct preliminary screening of partial discharge according to the actual use of the cable, which easily causes ineffective workload or heavy workload.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: an online detection system based on cable partial discharge positioning, comprising a screening module, a detection module, a compensation module and a display module;

[0006] The screening module performs a first segmentation on the cable to obtain sub-cables, performs a first numbering on the sub-cables, obtains the current angular frequency, cable insulation resistance, cable dielectric loss angle and cable capacitance corresponding to the sub-cables, calculates the tangent value of the cable dielectric loss angle, calculates the cable attenuation factor, sends a first positioning signal according to the cable attenuation factor, obtains the sub-cable number corresponding to the first positioning signal, reorders the sub-cable number corresponding to the first positioning signal, obtains the task number, sends it according to the task number, detects the parameters of the corresponding sub-cable, and automatically generates a first spectrum diagram;

[0007] The detection module obtains a partial discharge spectrum diagram, calculates the similarity between the first spectrum diagram and the partial discharge spectrum diagram, sets a similarity threshold, compares the similarity with the similarity threshold, sends a second positioning signal or a first jump signal according to the comparison result, and jumps to the next task number when the similarity is less than the similarity threshold;

[0008] The compensation module performs a first mark on the partial discharge spectrum diagram, obtains the first spectrum diagram, compares the first spectrum diagram with the marked partial discharge spectrum diagram, obtains the overlapping part and the non-overlapping part, calculates the ratio of the non-overlapping part to the area of ​​the first spectrum diagram, records it as the interference degree, sends a first frequency control signal according to the interference degree, continuously controls the frequency of the ultra-high frequency sensor to obtain the ideal detection frequency, obtains the first number of the sub-cable corresponding to the second positioning signal, performs a second segmentation on the sub-cable to obtain refined segments, performs a second number on the refined segments, detects the refined segments according to the ideal detection frequency, obtains the partial discharge amplitude, selects the partial discharge amplitude with the largest value, and sets the corresponding second number as the partial discharge fault point;

[0009] The display module is used to display the coordinates of the partial discharge fault point, the partial discharge type and the second number.

[0010] As a preferred solution of the online detection system based on cable partial discharge positioning described in the present invention, wherein: the screening module performs a first segmentation on the cable to obtain sub-cables, and first numbers the sub-cables, wherein the first number is represented by Di, wherein i is a natural number, and the length, width and height of the area to be detected are respectively the x-coordinate, the y-coordinate and the z-coordinate, and a three-dimensional space coordinate system is established;

[0011] The current angular frequency, cable insulation resistance, cable dielectric loss angle and cable capacitance corresponding to the sub-cable are obtained, the tangent value of the cable dielectric loss angle is calculated by the tangent formula, and the cable attenuation factor is calculated. The calculation expression of the cable attenuation factor is:

[0012]

[0013] Among them, α i is the cable attenuation factor of the ith sub-cable, R i is the cable insulation resistance of the ith sub-cable, ω is the current angular frequency, C i is the capacitance of the ith sub-cable, and tanδ is the tangent of the cable dielectric loss angle.

[0014] As a preferred solution of the online detection system based on cable partial discharge positioning described in the present invention, wherein: the screening module traverses the cable attenuation factors, sorts the cable attenuation factors in descending order, sets the first value as the cable attenuation factor threshold, selects the sub-cable whose value is greater than or equal to the cable attenuation factor threshold, obtains the corresponding first number, records it as the operation number, sends the first positioning signal according to the operation number, and the ultra-high frequency sensor is installed according to the operation number, respectively installed at both ends of the operation number, and the installation is represented as an installation with flexible mobility;

[0015] The first number of the sub-cable corresponding to the operation number is obtained, and the first number is reordered to obtain a task number. The generation logic of the task number includes:

[0016] Obtaining the cable attenuation factor corresponding to the first number, sorting the cable attenuation factors in descending order, updating the first number of the cable attenuation factor with the largest value to 1, and increasing the updated value of the first number according to the decreasing cable attenuation factor to obtain a task number, wherein the task number is a natural number;

[0017] According to the task sequence number, the parameters of the corresponding sub-cable are detected, the parameters of the sub-cable include the partial discharge amplitude and the partial discharge frequency, and the first spectrum diagram is automatically generated.

[0018] As a preferred solution of the online detection system based on cable partial discharge positioning described in the present invention, wherein: the detection module calls the cable partial discharge database, inputs the partial discharge type into the cable partial discharge database, obtains the corresponding partial discharge spectrum diagram according to the partial discharge type, extracts the shape feature quantity of each partial discharge spectrum diagram, and records it as the first feature quantity;

[0019] Extract the shape feature of the first spectrum graph and record it as the second feature. Calculate the similarity between the first feature and the second feature by using the cosine similarity formula. Set the second value as the similarity threshold. Compare the similarity with the similarity threshold to obtain a comparison result, wherein the comparison result includes that the similarity is less than the similarity threshold and that the similarity is greater than or equal to the similarity threshold. Send the second positioning signal or the first jump signal according to the comparison result.

[0020] As a preferred solution of the online detection system based on cable partial discharge positioning described in the present invention, when the similarity is less than the similarity threshold, jump to the next task number;

[0021] When the similarity is greater than or equal to the similarity threshold, the similarities are traversed, the similarities are sorted in descending order, the similarity with the largest value is selected, the corresponding partial discharge type is recorded as the current partial discharge type, and the second positioning signal is sent.

[0022] As a preferred solution of the online detection system based on cable partial discharge positioning described in the present invention, wherein: the compensation module receives the second positioning signal, performs a first mark on the partial discharge spectrum diagram, the first mark is represented by a color block of a first color value, obtains a first spectrum diagram, compares the first spectrum diagram with the marked partial discharge spectrum diagram, and obtains an overlapping part and a non-overlapping part;

[0023] Obtain the area of ​​the first spectrum graph, calculate the ratio of the non-overlapping part to the area of ​​the first spectrum graph, record it as the interference degree, set the third value as the interference degree threshold, compare the interference degree with the interference degree threshold, and when the interference degree is greater than or equal to the interference degree threshold, send a first frequency control signal.

[0024] As a preferred solution of the online detection system based on cable partial discharge positioning described in the present invention, wherein: the compensation module continuously controls the frequency of the ultra-high frequency sensor according to the first frequency control signal, sets the fourth value as the control amount, and continuously controls the frequency of the ultra-high frequency sensor with multiples of the control amount as the increase or decrease, and continuously calculates the interference degree after control, and the multiples of the control amount are natural numbers, until the interference degree after control is less than or equal to the upper limit of the interference degree, stops sending the first frequency control signal, and obtains a new ultra-high frequency sensor frequency, which is recorded as the ideal detection frequency.

[0025] As a preferred solution of the online detection system based on cable partial discharge positioning described in the present invention, wherein: the compensation module obtains the first number of the sub-cable corresponding to the second positioning signal, performs a second segmentation on the sub-cable to obtain refined segments, and performs a second numbering on the refined segments, the second number corresponds to the first number, and the second number is represented by Q ij , where j is a natural number. The refined segment is detected according to the ideal detection frequency to obtain the partial discharge amplitude. The partial discharge amplitude with the largest value is selected and its corresponding second number is set as the partial discharge fault point.

[0026] As a preferred solution of the online detection system based on cable partial discharge positioning described in the present invention, the positioning logic of the partial discharge fault point includes:

[0027] Obtain the second number of the refined segment, the corresponding head end coordinates and tail end coordinates, or the first number of the sub-cable where the refined segment is located, move the ultra-high frequency sensors at both ends of the sub-cable to the head end coordinates and tail end coordinates of the refined segment, detect the refined segment, obtain the partial discharge amplitude of the refined segment, traverse the partial discharge amplitudes, sort the partial discharge amplitudes in descending order, select the refined segment corresponding to the largest partial discharge amplitude and its second number, or the midpoint of the refined segment corresponding to the largest partial discharge amplitude, set the midpoint as the partial discharge fault point, and obtain the coordinates of the partial discharge fault point.

[0028] As a preferred solution of the online detection system based on cable partial discharge positioning described in the present invention, wherein: the display module is used to display the coordinates of the partial discharge fault point, the partial discharge type and the second number through an OLED display screen.

[0029] The beneficial effects of the present invention are as follows: by subdividing the cable into sub-cables and numbering them, the local discharge fault point can be accurately located, the detection accuracy is improved, the online detection module acquires and analyzes the local discharge spectrum in real time, quickly responds to changes in the cable condition, and ensures that potential problems are discovered in a timely manner; by calculating the interference degree, the frequency of the ultra-high frequency sensor can be dynamically adjusted to reduce the impact of interference on the detection results and ensure the validity of the signal; the spectrum diagram and task number management are automatically generated, the operating process is simplified, work efficiency is improved, and human errors are reduced; the coordinates and type of the local discharge fault point are intuitively presented, so that maintenance personnel can quickly identify the problem and take corresponding measures, greatly improving the safety and reliability of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the basic flow of an online detection system based on cable partial discharge positioning provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings. It is obvious that the described embodiments are only part of the embodiments of the present invention, but not all of the embodiments.

[0032] Example, see Figure 1 , as one embodiment of the present invention, provides an online detection system based on cable partial discharge positioning, including a screening module, a detection module, a compensation module and a display module;

[0033] The screening module performs a first segmentation on the cable to obtain sub-cables, performs a first numbering on the sub-cables, obtains the current angular frequency, cable insulation resistance, cable dielectric loss angle and cable capacitance corresponding to the sub-cables, calculates the tangent value of the cable dielectric loss angle, calculates the cable attenuation factor, sends a first positioning signal according to the cable attenuation factor, obtains the sub-cable number corresponding to the first positioning signal, reorders the sub-cable number corresponding to the first positioning signal, obtains the task number, sends it according to the task number, detects the parameters of the corresponding sub-cable, and automatically generates a first spectrum diagram;

[0034] The detection module obtains a partial discharge spectrum diagram, calculates the similarity between the first spectrum diagram and the partial discharge spectrum diagram, sets a similarity threshold, compares the similarity with the similarity threshold, sends a second positioning signal or a first jump signal according to the comparison result, and jumps to the next task number when the similarity is less than the similarity threshold;

[0035] The compensation module performs a first mark on the partial discharge spectrum diagram, obtains the first spectrum diagram, compares the first spectrum diagram with the marked partial discharge spectrum diagram, obtains the overlapping part and the non-overlapping part, calculates the ratio of the non-overlapping part to the area of ​​the first spectrum diagram, records it as the interference degree, sends a first frequency control signal according to the interference degree, continuously controls the frequency of the ultra-high frequency sensor to obtain the ideal detection frequency, obtains the first number of the sub-cable corresponding to the second positioning signal, performs a second segmentation on the sub-cable to obtain refined segments, performs a second number on the refined segments, detects the refined segments according to the ideal detection frequency, obtains the partial discharge amplitude, selects the partial discharge amplitude with the largest value, and sets the corresponding second number as the partial discharge fault point;

[0036] The display module is used to display the coordinates of the partial discharge fault point, the partial discharge type and the second number.

[0037] The present invention can accurately locate the partial discharge fault point by subdividing the cable into sub-cables and numbering them, thereby improving the accuracy of detection. The online detection module acquires and analyzes the partial discharge spectrum in real time, quickly responds to changes in the cable condition, and ensures that potential problems are discovered in a timely manner. By calculating the interference degree, the frequency of the ultra-high frequency sensor can be dynamically adjusted to reduce the impact of interference on the detection results and ensure the validity of the signal. The spectrum diagram and task sequence number management are automatically generated, which simplifies the operating process, improves work efficiency, reduces human errors, and intuitively presents the coordinates and type of the partial discharge fault point, so that maintenance personnel can quickly identify the problem and take corresponding measures, thereby greatly improving the safety and reliability of the cable.

[0038] The screening module performs a first segmentation on the cable to obtain sub-cables, and first numbers the sub-cables, wherein the first number is represented by Di, wherein i is a natural number, and the length, width and height of the area to be detected are respectively the x-coordinate, the y-coordinate and the z-coordinate, to establish a three-dimensional space coordinate system;

[0039] The current angular frequency, cable insulation resistance, cable dielectric loss angle and cable capacitance corresponding to the sub-cable are obtained, the tangent value of the cable dielectric loss angle is calculated by the tangent formula, and the cable attenuation factor is calculated. The calculation expression of the cable attenuation factor is:

[0040]

[0041] Among them, α i is the cable attenuation factor of the ith sub-cable, R i is the cable insulation resistance of the ith sub-cable, ω is the current angular frequency, C i is the capacitance of the ith sub-cable, and tanδ is the tangent of the cable dielectric loss angle.

[0042] In specific implementation, by dividing the cable into sub-cables and performing three-dimensional spatial coordinate modeling, a detailed analysis of the cable status can be achieved, which is helpful for fault location, and a variety of electrical parameters can be obtained, such as current angular frequency, insulation resistance, etc., and the cable attenuation factor can be calculated. The health status of the cable can be comprehensively evaluated. The expression for calculating the cable attenuation factor provides an important basis for subsequent fault detection, which helps to improve positioning accuracy and reduce false alarm rate. Automated processing reduces manual intervention, improves work efficiency and accuracy, and makes online monitoring more efficient.

[0043] The screening module traverses the cable attenuation factors, sorts the cable attenuation factors in descending order, sets the first value as the cable attenuation factor threshold, selects the sub-cable whose value is greater than or equal to the cable attenuation factor threshold, obtains the corresponding first number, records it as the operation number, sends the first positioning signal according to the operation number, and the ultra-high frequency sensor is installed according to the operation number, respectively, and is installed at both ends of the operation number, and the installation is represented as an installation with flexible mobility;

[0044] The first number of the sub-cable corresponding to the operation number is obtained, and the first number is reordered to obtain a task number. The generation logic of the task number includes:

[0045] Obtaining the cable attenuation factor corresponding to the first number, sorting the cable attenuation factors in descending order, updating the first number of the cable attenuation factor with the largest value to 1, and increasing the updated value of the first number according to the decreasing cable attenuation factor to obtain a task number, wherein the task number is a natural number;

[0046] According to the task sequence number, the parameters of the corresponding sub-cable are detected, the parameters of the sub-cable include the partial discharge amplitude and the partial discharge frequency, and the first spectrum diagram is automatically generated.

[0047] In specific implementation, by sorting the cable attenuation factors in descending order, the system can quickly identify the sub-cables that need the most attention and improve the priority of fault location. After setting the cable attenuation factor threshold, the system can flexibly select the sub-cables that need to be installed with ultra-high frequency sensors to achieve dynamic monitoring and effectively respond to changing cable conditions. Through the automatic generation and update of task numbers, the system can efficiently arrange detection tasks, reduce manual intervention, and improve operational efficiency. Spectrum diagrams are automatically generated during the detection process to facilitate rapid analysis and decision-making, making fault location more intuitive and efficient.

[0048] The detection module calls the cable partial discharge database, inputs the partial discharge type into the cable partial discharge database, obtains the corresponding partial discharge spectrum according to the partial discharge type, extracts the shape feature of each partial discharge spectrum, and records it as the first feature;

[0049] Extract the shape feature of the first spectrum graph and record it as the second feature. Calculate the similarity between the first feature and the second feature by using the cosine similarity formula. Set the second value as the similarity threshold. Compare the similarity with the similarity threshold to obtain a comparison result, wherein the comparison result includes that the similarity is less than the similarity threshold and that the similarity is greater than or equal to the similarity threshold. Send the second positioning signal or the first jump signal according to the comparison result.

[0050] In the specific implementation, by extracting the shape characteristics of the partial discharge spectrum diagram, the characteristics of the partial discharge signal can be deeply analyzed to enhance the accuracy of fault identification. The cosine similarity formula is used to quantify the similarity between different spectrum diagrams, making the fault comparison more scientific and reliable. After setting the similarity threshold, the monitoring strategy can be flexibly adjusted according to the comparison results, and the positioning or jump signal can be sent in time to improve the response speed. Based on the similarity analysis, normal signals and fault signals can be effectively distinguished, providing maintenance personnel with accurate decision-making basis.

[0051] When the similarity is less than the similarity threshold, jump to the next task number;

[0052] When the similarity is greater than or equal to the similarity threshold, the similarities are traversed, the similarities are sorted in descending order, the similarity with the largest value is selected, the corresponding partial discharge type is recorded as the current partial discharge type, and the second positioning signal is sent.

[0053] In specific implementation, when the similarity is less than the threshold, it automatically jumps to the next task number to avoid unnecessary interference and improve detection efficiency. By sorting the similarity in descending order, the most relevant type of partial discharge can be quickly identified to ensure attention to key signals, thereby optimizing fault location. The operation can be dynamically adjusted according to changes in similarity, and different monitoring situations can be responded to in a timely manner, improving the overall reaction capability, selecting the type of partial discharge corresponding to the similarity with the largest value, ensuring the accuracy of the positioning signal, and thus improving the reliability of fault diagnosis.

[0054] The compensation module receives the second positioning signal, performs a first mark on the partial discharge spectrum diagram, wherein the first mark is represented by a color block of a first color value, obtains a first spectrum diagram, and compares the first spectrum diagram with the marked partial discharge spectrum diagram to obtain an overlapping part and a non-overlapping part;

[0055] Obtain the area of ​​the first spectrum graph, calculate the ratio of the non-overlapping part to the area of ​​the first spectrum graph, record it as the interference degree, set the third value as the interference degree threshold, compare the interference degree with the interference degree threshold, and when the interference degree is greater than or equal to the interference degree threshold, send a first frequency control signal.

[0056] In the specific implementation, by first marking the partial discharge spectrum diagram, intuitive visualization is achieved, which is convenient for rapid identification of key areas and abnormal signals. Comparing the overlapping and non-overlapping parts helps to deeply understand the relationship between signals and improve the accuracy of fault analysis. Calculating the ratio of the non-overlapping part to the spectrum diagram area provides a quantitative basis for judging signal interference and enhances the scientific nature of monitoring. Based on the comparison of the interference degree and the threshold, the system can automatically send frequency control signals, improve signal quality, and optimize the monitoring effect.

[0057] The compensation module continuously controls the frequency of the ultra-high frequency sensor according to the first frequency control signal, sets the fourth value as the control amount, continuously controls the frequency of the ultra-high frequency sensor with the multiple of the control amount as the increase or decrease, and continuously calculates the interference degree after control, where the multiple of the control amount is a natural number, until the interference degree after control is less than or equal to the upper limit of the interference degree, stops sending the first frequency control signal, and obtains a new ultra-high frequency sensor frequency, which is recorded as the ideal detection frequency.

[0058] In specific implementation, through continuous regulation of the frequency of the ultra-high frequency sensor, it is possible to adapt to changes in the signal environment in real time, optimize the monitoring effect, and set the multiples of the regulation amount to natural numbers, making the frequency regulation process more detailed and able to accurately adjust to achieve the ideal state. During the regulation process, the interference degree is continuously calculated to ensure the effectiveness and timeliness of the adjustment measures and improve the reliability of monitoring. The new frequency finally obtained is used as the ideal detection frequency, which provides an efficient and stable benchmark for subsequent monitoring and improves the overall system performance.

[0059] The compensation module obtains the first number of the sub-cable corresponding to the second positioning signal, performs a second segmentation on the sub-cable to obtain refined segments, and performs a second numbering on the refined segments, wherein the second number corresponds to the first number, and the second number is represented by Qij, wherein j is a natural number, and the refined segments are detected according to the ideal detection frequency to obtain the partial discharge amplitude, and the partial discharge amplitude with the largest value is selected, and the corresponding second number is set as the partial discharge fault point.

[0060] In specific implementation, by performing a second segmentation on the sub-cable, more detailed monitoring can be achieved and the ability to locate partial discharge faults can be improved. The correspondence between the second number and the first number makes the organization of the monitoring data more systematic, which is helpful for subsequent analysis and recording. Refined segmented detection is performed according to the ideal detection frequency to ensure that the obtained partial discharge amplitude has high accuracy and improve the reliability of fault identification. By selecting the partial discharge amplitude with the largest value, the partial discharge fault point can be quickly determined, and the response speed and fault handling efficiency can be improved.

[0061] The locating logic of the partial discharge fault point includes:

[0062] Obtain the second number of the refined segment, the corresponding head end coordinates and tail end coordinates, or the first number of the sub-cable where the refined segment is located, move the ultra-high frequency sensors at both ends of the sub-cable to the head end coordinates and tail end coordinates of the refined segment, detect the refined segment, obtain the partial discharge amplitude of the refined segment, traverse the partial discharge amplitudes, sort the partial discharge amplitudes in descending order, select the refined segment corresponding to the largest partial discharge amplitude and its second number, or the midpoint of the refined segment corresponding to the largest partial discharge amplitude, set the midpoint as the partial discharge fault point, and obtain the coordinates of the partial discharge fault point.

[0063] In specific implementation, by obtaining the number and coordinates of the refined segment, the partial discharge fault point can be accurately located, the reliability of fault detection can be improved, and the ultra-high frequency sensor can be moved to the head and tail ends of the refined segment to ensure comprehensive detection coverage. The partial discharge amplitude obtained is more accurate, the partial discharge amplitude is sorted in descending order, the most serious fault point can be quickly identified, and the fault response time can be optimized.

[0064] The display module is used to display the coordinates of the partial discharge fault point, the partial discharge type and the second number through the OLED display screen.

[0065] In specific implementation, the coordinates of the partial discharge fault point, the type of partial discharge and the second number can be clearly displayed through the OLED display screen, thereby improving the intuitiveness of information transmission.

[0066] The present invention can accurately locate the partial discharge fault point by subdividing the cable into sub-cables and numbering them, thereby improving the accuracy of detection. The online detection module acquires and analyzes the partial discharge spectrum in real time, quickly responds to changes in the cable condition, and ensures that potential problems are discovered in a timely manner. By calculating the interference degree, the frequency of the ultra-high frequency sensor can be dynamically adjusted to reduce the impact of interference on the detection results and ensure the validity of the signal. The spectrum diagram and task sequence number management are automatically generated, which simplifies the operating process, improves work efficiency, reduces human errors, and intuitively presents the coordinates and type of the partial discharge fault point, so that maintenance personnel can quickly identify the problem and take corresponding measures, thereby greatly improving the safety and reliability of the cable.

[0067] It should be understood by those skilled in the art that the embodiments of the present invention can be provided as methods, systems or computer program products. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media containing computer-usable program codes. Among them, the storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (Static Random Access Memory, referred to as SRAM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, referred to as EEPROM), erasable programmable read-only memory (Erasable Programmable Read Only Memory, referred to as EPROM), programmable read-only memory (Programmable Red-Only Memory, referred to as PROM), read-only memory (Read-Only Memory, referred to as ROM), magnetic memory, flash memory, disk or optical disk. These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0068] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. The online detection system based on cable partial discharge positioning is characterized by: It includes a screening module, a detection module, a compensation module and a display module; The screening module performs a first segmentation on the cable to obtain sub-cables, performs a first numbering on the sub-cables, obtains the current angular frequency, cable insulation resistance, cable dielectric loss angle and cable capacitance corresponding to the sub-cables, calculates the tangent value of the cable dielectric loss angle, calculates the cable attenuation factor, sends a first positioning signal according to the cable attenuation factor, obtains the sub-cable number corresponding to the first positioning signal, reorders the sub-cable number corresponding to the first positioning signal, obtains the task number, sends it according to the task number, detects the parameters of the corresponding sub-cable, and automatically generates a first spectrum diagram; The detection module obtains a partial discharge spectrum diagram, calculates the similarity between the first spectrum diagram and the partial discharge spectrum diagram, sets a similarity threshold, compares the similarity with the similarity threshold, sends a second positioning signal or a first jump signal according to the comparison result, and jumps to the next task number when the similarity is less than the similarity threshold; The compensation module performs a first mark on the partial discharge spectrum diagram, obtains the first spectrum diagram, compares the first spectrum diagram with the marked partial discharge spectrum diagram, obtains the overlapping part and the non-overlapping part, calculates the ratio of the non-overlapping part to the area of ​​the first spectrum diagram, records it as the interference degree, sends a first frequency control signal according to the interference degree, continuously controls the frequency of the ultra-high frequency sensor to obtain the ideal detection frequency, obtains the first number of the sub-cable corresponding to the second positioning signal, performs a second segmentation on the sub-cable to obtain refined segments, performs a second number on the refined segments, detects the refined segments according to the ideal detection frequency, obtains the partial discharge amplitude, selects the partial discharge amplitude with the largest value, and sets the corresponding second number as the partial discharge fault point; The display module is used to display the coordinates of the partial discharge fault point, the type of partial discharge and the second number.

2. The online detection system based on cable partial discharge positioning according to claim 1, characterized in that: The screening module performs a first segmentation on the cable to obtain sub-cables, and first numbers the sub-cables, wherein the first number is represented by Di, wherein i is a natural number, and the length, width and height of the area to be detected are respectively the x-coordinate, the y-coordinate and the z-coordinate, to establish a three-dimensional space coordinate system; The current angular frequency, cable insulation resistance, cable dielectric loss angle and cable capacitance corresponding to the sub-cable are obtained, the tangent value of the cable dielectric loss angle is calculated by the tangent formula, and the cable attenuation factor is calculated. The calculation expression of the cable attenuation factor is: Among them, α i is the cable attenuation factor of the ith sub-cable, R i is the cable insulation resistance of the ith sub-cable, ω is the current angular frequency, C i is the capacitance of the ith sub-cable, and tanδ is the tangent of the cable dielectric loss angle.

3. The online detection system based on cable partial discharge positioning as claimed in claim 2, characterized in that: The screening module traverses the cable attenuation factors, sorts the cable attenuation factors in descending order, sets the first value as the cable attenuation factor threshold, selects the sub-cable whose value is greater than or equal to the cable attenuation factor threshold, obtains the corresponding first number, records it as the operation number, sends the first positioning signal according to the operation number, and the ultra-high frequency sensor is installed according to the operation number, respectively, and is installed at both ends of the operation number, and the installation is represented as an installation with flexible mobility; The first number of the sub-cable corresponding to the operation number is obtained, and the first number is reordered to obtain a task number. The generation logic of the task number includes: Obtaining the cable attenuation factor corresponding to the first number, sorting the cable attenuation factors in descending order, updating the first number of the cable attenuation factor with the largest value to 1, and increasing the updated value of the first number according to the decreasing cable attenuation factor to obtain a task number, wherein the task number is a natural number; According to the task sequence number, the parameters of the corresponding sub-cable are detected, the parameters of the sub-cable include the partial discharge amplitude and the partial discharge frequency, and the first spectrum diagram is automatically generated.

4. The online detection system based on cable partial discharge positioning according to claim 1, characterized in that: The detection module calls the cable partial discharge database, inputs the partial discharge type into the cable partial discharge database, obtains the corresponding partial discharge spectrum according to the partial discharge type, extracts the shape feature of each partial discharge spectrum, and records it as the first feature; Extract the shape feature of the first spectrum graph and record it as the second feature. Calculate the similarity between the first feature and the second feature by using the cosine similarity formula. Set the second value as the similarity threshold. Compare the similarity with the similarity threshold to obtain a comparison result, wherein the comparison result includes that the similarity is less than the similarity threshold and that the similarity is greater than or equal to the similarity threshold. Send the second positioning signal or the first jump signal according to the comparison result.

5. The online detection system based on cable partial discharge positioning as claimed in claim 4, characterized in that: When the similarity is less than the similarity threshold, jump to the next task number; When the similarity is greater than or equal to the similarity threshold, the similarities are traversed, the similarities are sorted in descending order, the similarity with the largest value is selected, the corresponding partial discharge type is recorded as the current partial discharge type, and the second positioning signal is sent.

6. The online detection system based on cable partial discharge positioning according to claim 1, characterized in that: The compensation module receives the second positioning signal, performs a first mark on the partial discharge spectrum diagram, wherein the first mark is represented by a color block of a first color value, obtains a first spectrum diagram, and compares the first spectrum diagram with the marked partial discharge spectrum diagram to obtain an overlapping part and a non-overlapping part; Obtain the area of ​​the first spectrum graph, calculate the ratio of the non-overlapping part to the area of ​​the first spectrum graph, record it as the interference degree, set the third value as the interference degree threshold, compare the interference degree with the interference degree threshold, and when the interference degree is greater than or equal to the interference degree threshold, send a first frequency control signal.

7. The online detection system based on cable partial discharge positioning according to claim 6, characterized in that: The compensation module continuously controls the frequency of the ultra-high frequency sensor according to the first frequency control signal, sets the fourth value as the control amount, continuously controls the frequency of the ultra-high frequency sensor with the multiple of the control amount as the increase or decrease, and continuously calculates the interference degree after control, where the multiple of the control amount is a natural number, until the interference degree after control is less than or equal to the upper limit of the interference degree, stops sending the first frequency control signal, and obtains a new ultra-high frequency sensor frequency, which is recorded as the ideal detection frequency.

8. The online detection system based on cable partial discharge positioning according to claim 7, characterized in that: The compensation module obtains the first number of the sub-cable corresponding to the second positioning signal, performs a second segmentation on the sub-cable to obtain refined segments, and performs a second numbering on the refined segments, wherein the second number corresponds to the first number, and the second number is represented by Q ij , where j is a natural number. The refined segment is detected according to the ideal detection frequency to obtain the partial discharge amplitude. The partial discharge amplitude with the largest value is selected and its corresponding second number is set as the partial discharge fault point.

9. The online detection system based on cable partial discharge positioning according to claim 8, characterized in that: The locating logic of the partial discharge fault point includes: Obtain the second number of the refined segment, the corresponding head end coordinates and tail end coordinates, or the first number of the sub-cable where the refined segment is located, move the ultra-high frequency sensors at both ends of the sub-cable to the head end coordinates and tail end coordinates of the refined segment, detect the refined segment, obtain the partial discharge amplitude of the refined segment, traverse the partial discharge amplitudes, sort the partial discharge amplitudes in descending order, select the refined segment corresponding to the largest partial discharge amplitude and its second number, or the midpoint of the refined segment corresponding to the largest partial discharge amplitude, set the midpoint as the partial discharge fault point, and obtain the coordinates of the partial discharge fault point.

10. The online detection system based on cable partial discharge positioning according to claim 1, characterized in that: The display module is used to display the coordinates of the partial discharge fault point, the partial discharge type and the second number through the OLED display screen.

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